Partner with Alloway for UCMR 4

As an EPA UCMR 4 approved laboratory, we want to serve as a knowledge reference as you implement your UCMR 4 monitoring schedule.

Click this link for a copy of Alloway’s UCMR 4 certification.

Monitoring for the fourth Unregulated Contaminant Monitoring Regulation (UCMR 4) is set to begin in January 2018 and will run through December 2020. The monitoring includes 30 contaminants and will affect many public water systems across the nation. 

The UCMR 4 list of contaminants includes 10 cyanotoxins:

  • Total Microcystins by EPA method 546
  • Six specific microcystin congeners and nodularin by EPA method 544
  • Anatoxin-a and cylindrospermopsin by EPA method 545

All large surface water and ground water under the direct influence of surface water systems (serving more than 10,000 people) will monitor for these cyanotoxins, as will a random selection of 800 smaller water systems. 

Samples for cyanotoxins will be collected twice a month for four consecutive months (total of eight sampling events), during the monitoring timeframe of March through November. Each of the three methods will be collected at the entry point to the distribution system (EPTDS), but the analysis for the six specific microcystin congeners and nodularin by Method 544 is only required if the result for Total Microcystins by Method 546 is greater than or equal to 0.3 μg/L. Sample collection for microcystins will take place at the entry point to the distribution system (EPTDS).

In addition to the 10 cyanotoxins, all large water systems (serving more than 10,000 people) will be required to monitor for 20 additional contaminants. This applies to surface water systems, ground water under the direct influence of surface water systems, and ground water systems. There will also be 800 randomly selected smaller water systems required to participate.  

Below is the list of the 20 additional contaminants to be monitored:

  • Two metals (germanium and manganese) by EPA method 200.8, ASTM D5673-10, or SM 3125
  • Eight Pesticides and One Pesticide Manufacturing Byproduct by EPA method 525.3
  • Three Brominated Haloacetic Acid (HAA) Groups by EPA methods 552.3 or 557
  • Three Alcohols by EPA method 541
  • Three Other Semivolatile Chemicals by EPA method 530
  • HAA indicators: Total Organic Carbon SM 5310B and Bromide EPA method 300.1

Sampling frequency for the 20 additional contaminants will depend on the source water. Surface water and ground water under the direct influence of surface water systems will sample four consecutive quarters over the course of 12 months; a total of four sampling events. Ground water systems will sample twice over the course of 12 months; a total of two sampling events. 

Sample collection for the metals, pesticides, alcohols, and SVOCs will take place at the entry point to the distribution system (EPTDS). Sampling for the HAA groups must be “taken at the D/DBPRs sampling locations described in 40 CFR 141.622.” TOC and Bromide must be collected at a location prior to any treatment and must be collected at the same time as the HAA samples. The US EPA states, “SW and GWUDI systems subject to the D/DBPR TOC monitoring must use their D/DBPRs TOC source water sampling site(s) from 40 CFR 141.132. SW and GWUDI systems that are not subject to D/DBPRs TOC monitoring must use their Long Term 2 Enhanced Surface Water Treatment Rule (LT2) source water sampling site(s) (40 CFR 141.703). GW systems that are subject to the D/DBPRs collect TOC and bromide samples at the influents entering their treatment train. Consecutive systems (PWSs that purchase 100 percent of their water) are not required to collect source water samples for TOC or bromide analyses.”(US EPA UCMR 4, HAA Groups – Fact Sheet for Assessment Monitoring, December 2016).

Monitoring schedules for UCMR 4 are available through the EPA’s CDX website. Below are the tests required under each assessment monitoring (AM) schedule:

  • AM 1: Pesticides, Alcohols, SVOC’s and Metals
  • AM 2: Haloacetic Acids, TOC and Bromide
  • AM 3: Microcystins 

No matter what your monitoring requirements are, Alloway can serve as your UCMR 4 project manager. Contact us at support@alloway.com for a quote.

To learn more about UCMR 4, visit the US EPA UCMR 4 website.